Patents by Inventor Koki SHIBAHARA

Koki SHIBAHARA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • CHROMATIC DISPERSION ESTIMATING CIRCUIT, OPTICAL RECEPTION DEVICE AND CHROMATIC DISPERSION AMOUNT ESTIMATING METHOD
    Publication number: 20180252614
    Abstract: A Fourier-transformer performs Fourier transform on a filter coefficient output from an adaptive equalizer which comprises a finite impulse response filter of N taps (N represents an integer of 2 or more) in a time direction. An eigenvalue sum calculator integrates a frequency-differentiation result of the Fourier-transformed filter coefficient and a complex conjugate of the Fourier-transformed filter coefficient to calculate a matrix, and calculates a sum of two eigenvalues of the matrix. A proportionality factor calculator calculates a proportionality factor for frequency from the sum of the two eigenvalues.
    Type: Application
    Filed: October 4, 2016
    Publication date: September 6, 2018
    Inventors: Etsushi YAMAZAKI, Tomohiro TAKAMUKU, Yuki YOSHIDA, Mitsuteru YOSHIDA, Koki SHIBAHARA, Kengo HORIKOSHI, Yoshiaki KISAKA